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Pressure exponent of burning rate

In general, the burning rate of an energetic material is seen to increase linearly with increasing pressure in an hr p versus hr rplot represented by Eq. (3.68) at constant initial temperature Tq. Thus, the pressure sensitivity of burning rate at a constant initial temperature, n, is defined by [Pg.64]


Though both propellants contain equal amounts of NC and NG, the burning rate of NC-NG-GAP is approximately 70% higher than that of NC-NG-DEP at Tq = 293 K. The pressure exponent of burning rate remains relatively unchanged at = 0.7 by the replacement of DEP with GAP. However, the temperature sensitivity of burning rate defined in Eq. (3.73) is increased significantly from 0.0038 K" to 0.0083 K- ... [Pg.160]

Table 6.10 Overall reaction order, m, in the dark zone determined from the pressure exponent of burning rate, n, and the dark zone index, d. Table 6.10 Overall reaction order, m, in the dark zone determined from the pressure exponent of burning rate, n, and the dark zone index, d.
Fig. 7.13 shows the effect of the particle size of AP on burning rate.I l The propellants have the composition ap(0-80) and htpb(0-20). The AP particles are bimodal large-sized, with a 350 pm/200 pm mixture ratio of 4 3, and bimodal small-sized, with a 15 pm/3 pm mixture ratio of 4 3. The burning rate of the smaU-sized AP propellant is more than double that of the large-sized AP propellant. The pressure exponent of burning rate is 0.47 for the large-sized AP propellant and 0.59 for the small-sized AP propellant... [Pg.189]

It is well known that the super-rate burning of nitropolymer propellants diminishes with increasing pressure in the region 5-100 MPa and that the pressure exponent of burning rate decreases. - ] This burning rate mode is called plateau burning. As for these nitropolymer propellants catalyzed with LiF and C, HMX propellants catalyzed with LiF and C also show plateau burning. [Pg.215]

In general, pyrolants composed of a polymeric material and AN particles are smokeless in character, their burning rates are very low, and their pressure exponents of burning rate are high. However, black smoke is formed as i decreased and carbonaceous layers are formed on the burning surface. These carbonaceous layers are formed from the undecomposed polymeric materials used as the matrix of the pyrolant. When crystalline AN particles are mixed with GAP, GAP-AN pyrolants are formed. Since GAP burns by itself, the GAP used as a matrix for AN particles decomposes completely and bums with the oxidizer gases generated by the AN particles. [Pg.324]

Since the pressure exponent of burning rate is less than unity for conventional propellants, a becomes negative, and the burning becomes stable. In the case of n being greater than unity, a becomes positive, and increasingly oscillatory burning may occur. When n is very close to unity, a becomes approximately zero, and co can be determined from the approximation... [Pg.385]

Fig. 14.10 Pressure increase in a rocket motor versus pressure exponent of burning rate as a function of temperature sensitivity. Fig. 14.10 Pressure increase in a rocket motor versus pressure exponent of burning rate as a function of temperature sensitivity.
The mass generation rate in the gas generator is controlled by the variable flow system and the mixture ratio of fuel-rich gas to air in the ramburner is optimized. The burning rate is represented by the relationship r = ap", where r is the linear burning rate, p is the pressure, n is the pressure exponent of burning rate, and o is a con-... [Pg.447]

A high pressure exponent of burning rate approximately 0.7-0.9, but must be less than 1.0. [Pg.453]

The burning rate of propellants is one of the important parameters for the design of rocket motors. The burning rate is obtained as a function of pressure and of initial temperature, from which pressure exponent of burning rate and temperature sensitivity of burning rate are deduced. [Pg.491]

The pressure exponent of burning rate is commonly used to evaluate the effectiveness of catalysts in producing plateau and mesa burning.[1 -23] pressure ex-... [Pg.163]


See other pages where Pressure exponent of burning rate is mentioned: [Pg.64]    [Pg.115]    [Pg.143]    [Pg.143]    [Pg.149]    [Pg.162]    [Pg.163]    [Pg.169]    [Pg.219]    [Pg.252]    [Pg.320]    [Pg.321]    [Pg.324]    [Pg.327]    [Pg.346]    [Pg.410]    [Pg.416]    [Pg.430]    [Pg.450]    [Pg.451]    [Pg.453]    [Pg.454]    [Pg.64]    [Pg.115]    [Pg.143]    [Pg.143]    [Pg.149]    [Pg.162]    [Pg.169]    [Pg.219]    [Pg.252]    [Pg.320]   
See also in sourсe #XX -- [ Pg.53 , Pg.123 , Pg.142 , Pg.158 , Pg.207 , Pg.235 ]




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